The development of monitoring systems, which obtain and record image information when an event (e.g., an accident) occurs by using a monitoring camera or other devices, has advanced in recent years. It is thought that by using the monitoring system described above, if information, particularly from before the occurrence of an event, can be referenced, then investigating the cause of the event will be improved.
For example, Patent Literature 1 discloses a driving recorder that “includes a moving-image capturing unit that captures a moving image by using a camera incorporated in a mobile object; an image obtaining unit that obtains an image from the captured moving image in a predetermined sampling cycle; a specific-information obtaining unit that obtains information that is specific to the obtained image; a specific-information transmitting unit that transmits the obtained specific information to a predetermined server that gives a time stamp; an event detecting unit that detects the occurrence of an event; and a moving-image storing unit that has stored therein a moving image for at least a predetermined preceding recording time before the occurrence of an event when the event detecting unit detects the event”. This driving recorder records image information in a data storage unit and, at the same time, it continuously updates the moving image obtained by recording for a predetermined period of time before the present time until the present time.